The rule of the western Mongolian peoples lasted for about 400 years and had its origin with an "Alliance of the Four Oirat Tribes" (Dörböd Oirats = 4 Oirats): with the Dörbets (Dörböd, Dörbet), Dzungars (Jüün Ghar Ölöts, Eleuths), Khoshut (Khoshuud) and Torghuts (Torghuud).
The princes of the four tribes all had a different origin. The leaders of the Jüün Ghar, Dörbets and Khoit all were related in some way their clan name was Khoros; the leaders of the Khoshut claimed to be descendants of Jochi Qasar, one of Genghis Khan's brothers, and the Torghut leaders even claimed the old Kerait Khans as their ancestors. Sometimes also the Khoits who were dependent on the Dörbets as well as alliances with neighbouring tribes such as the Zachatschin, Bayids, Mangits and Darkhads and the Turkic tribes such as the Urianchai, Telenguets and the Shor people are mentioned. They lived in transportable round tents (yurts ger) and wandered with their herds (horses, cattle, sheep and camels) through the steppes ("grassland" between the Lake Balkhash and the Baikal as well as the steppes in the Mongolian area (Inner and Outer Mongolia)) such as their ancestors used to do. Under the rule of Genghis Khan, they were united with the tribes of the Keraits (since the 3rd and 5th century they had settled between the Orchon Valley and the River Kherlen), the Naimans (tribe of the Sekiz Oghuz) and the Merkits (they settled in the southeast of Siberia). Of course, also the tribes of the Eastern Mongols, the Khalka, Chahar and Türmed that had to suffer under the Manchurian leadership for a rather long time, belonged to that group.
- The Torghuts wandered, under Khu-Urluk (1616-1643 AC), at the beginning of the 17th century through Central Asia as far as the Volga estuary; for some time they were responsible for an imbalance of power in Eastern Europe. Only in the year 1771 a part moved back to the Ili area. The Torghuts, especially those who stayed behind at the Volga estuary, are today known under the name Kalmyks.
- The next to follow were the Dörbets under Dalay (died in 1637 AC), Dayan Ombo and others, as well as the independent group of the Khoshut under Khundelen (died in 1648 AC) and his nephew Ablay (died in 1672 AC). They are known to have settled in Siberia and at the Ural, where they acted repeatedly in alliance with the Khoshut against the Torghuts and other neighbouring tribes.
- The Khoshut spread their area of influence under Gurschri Khan († 1655/56), mainly as allies of the Yellow Church also in Tibet, until they had to give up this dominating position in 1717 AC; in 1723 they were integrated into China.
- Urianchai: Early settlers at the upper course of the Yenisey have been mentioned by the Chinese since the 7th century. Parts of them left the eastern Siberian, Manchurian and Altai area and established their own individual tribe, which was, in general, called Urianchai (the name was supposedly adopted from the Manchurian predecessors, the Jurchen people). It is, however, to be questioned whether there is given proof of Samojedian descent: the population of today may be rather seen as descendants of the Manchurian-Tungusic, Mongolian and Old Turkic community. They are also relatives of the Dywa in the Altai area who live in western Mongolia and Chinese Altai. They were nomads and cattle breeders, such as were all Turkic tribes. Furthermore, they are strongly influenced by the Mongolian culture and practise shamanism: they do, however, also believe in Buddhism. In this region, there are found mineral resources, and there is even given evidence of old-time iron processing. In the source area of the Yenisey, there still are living reindeer nomads (of Tungisic origin) and hunters (forest nomads).
Excavations in the Death Valley near Turan have proven that this area had been settled even by the Scythians (6th and 5th century BC).
In the 13th century the territory was conquered by Genghis Khan and subordinated to the leadership of the Yuan Dynasty (Kublai Khans). In the 16th and 17th century they were suppressed by the Oirats, the western tribes of the Mongols, the tribe of the Khotgoit and the Altan Khanate (the Khalka Princes). In the course of the centuries, also the Uyghurs and the Kirghiz ruled over this territory, before it became integral part of the Qing Dynasty of the Chinese Empire.
In the course of inner political revolts, the area which was then called "Outer Mongolia" (Uliassutai, today's Mongolia), also including the province Tannu-Urjanchai, ceded from China. Supported and backed by Tsarist Russia, there was developed a separatist movement which then in 1912 proclaimed Tannu-Tuva's independence. Two tribes south of the Tannu-ola Mountains, however, stayed under Mongolian rule based in Urga (today's Ulaanbaatar).
- The Buryats belong to the group of the Mongolian tribes settling farthest north, with their area of settlement being situated in Transbaikalia (eastern Siberia). They were also nomads and cattle breeders, such as the Tungusic people (Evenks) settling there; there are also to be mentioned the neighbouring Mongolian tribes, the Khalka and the Oirats. Their area of settlement circling the Baikal was integrated into the Russian Empire in 1689 and 1728 AC, this making them their tributaries. This was the beginning of a strong process of Russification, especially around the Lake Baikal and the Olchon region; mainly in connection with agriculture. Also Buddhism was on the rise.
- Daur Dahur: During the time of the Qing Dynasty, they moved and wandered a lot; originally, they had lived in Transbaikalia at the upper course of the Amur and in Central Mongolia. The hierarchy of the Daur people was clearly structured. Following the wedding ceremony, the groom moved to the bride's family without any legal claim. Each family had its own shaman. The Mongolian speaking Daur are also direct descendants of the Khitan in China in the region Xingjiang and in Pakistan.
The tribes, originally, settled in the Dzungarian Basin (Dzungaria; Xingjiang) and in the Amdo region at the Yellow River and the Yangtze Jiang. Their language and their culture are similar to those of the eastern neighbours, this is the Khalka. At the time of Genghis Khan, they were a western Mongolian tribe that dominated and controlled huge areas of Central Asia as a tribal confederation from the 12th to the 18th century. Each tribe ruled autonomously with a Noyon (prince) who, at the same time, also was the Chief Tayishim.
Some of the Oirat tribes lived at the upper course of the Yenisey on hunting and grass farming. When the central power was established in Mongolia in 1206 AC, the allies of the Jamukha Gurkhan surrendered to the federation leader Hutuha Beki, the Genghis Khan, and they helped, by means of battles as well as negotiations, integrating these forest and shepherd nomads in the area between Taiga and Irtysh (1207-1208 AC) into this central power. As a reward, Genghis Khan got two princesses married with two of Hutuha's sons. As a consequence, the Oirat princes assumed a special status among the united "Mongolian tribes" due to these relation on the basis of marriage. About 1400 AC. the Oirats settled down as horse breeders also in the Mongolian Altai.
After the Mongols had left China (Inner Mongolia end of the Yuan Dynasty in 1368 AC), the Oirats assumed a leading role among the Mongolian tribes in the very complicated conflicts (for example, death of the eastern Mongolian Khan Elbeg) after 1400 AC. So the Oirat leader Batula (also Mahamu) appointed the Khan Delbeg (ruled 1411-1414/15 AC) to his office. The Ming Emperor Yung-lo, however, was very dissatisfied with Batula's growing power, so he marched against him in 1414. Batula (Mahamu) fled to the river Tula (Ulaanbaatar), where he was finally killed. The rise of the Oirats was interrupted only for a very short period of time. His son Toghan und grandson Esen Taiji defended their area of influence from the river Ili (the point where they were successful in a number of battles against the Tschagatai Khans *Eastern Mongols*) as far as the Chinese frontier. The eastern Mongols (Genghisids) scarcely had more than a nominal dominance over Mongolia, and already Toghan Taiji is said to have tried to make himself Khan shortly before his death in 1439 AC. In the year 1449 AC, Esen Taiji succeeded in taking prisoner the Ming Emperor Zhengtong after a victory at Tumu (town in the northern Shanxi province). He was not, however, able to make further use of his success, and the only thing he could get was the ransom. Then Esen Taiji asked the nominal Mongol Khan Toyto Bugha (his brother-in-law, ruled 1439-1452 AC) to arrange his succession in favour of the Oirats. The Khan did not accept and was finally killed in this tribal war, in this way providing Esen Taiji with the opportunity to make himself Khan, although he was not an Eastern Mongol, "Genghisid"). But already in 1455 AC the Oirats got rid of him in the course of an internal conflict. Esen's successor was, as determined by Tarik-i-Rashid, his son Amasandji. But at this period of time, the Oirats appeared to have lost their family and internal cohesion, respectively, in spite of their big external success (for example, victory over the Usbeks in 1456/57 AC, another one over the Chagatei Khan Yunus, "Eastern Mongols"). So it was rather surprising that the representatives of the nominal Khans (see Manduchai) won in approx. 1468, and hence the Oirats spread under the different leaders into various directions. Under the leadership of Batu-Möngke-Dayan-Khan (ruled approx. 1470-1524 AC) the rule and reign of the Genghisids (Eastern Mongols) had a revival. Some defeats against the western Mongolian princes followed, and finally they were pushed from their throne in Karakorum into the Kobdo region in northwestern Mongolia. Altan Khan of the Dörbets 1552 ff. and Abdai Khan of the Khalka 1577 ff. offered the Oirat tribes at the end of the 16th century two possibilities: either submission or exodus. An epic, "The Route of Mongolian Sholui Ubashi Khong Tayiji" tells of the last victory of the Oirats over the first Khan of the Altan Khanat (about 1587 AC). At this time, many leaders lived scattered across the Irtysh, and approx. in 1603 their scouts roamed the land as far as the Khanat Chiwa at Lake Aral. Internal difficulties among the eastern Mongol princes, for the last time, took some pressure off the Oirats, and in the years 1606, 1623 and 1628/9 AC they won against the Khalka (eastern Mongols); the exodus, however, had become irreversible.
About 1615 the Oirats converted to Tibetan Buddhism, this resulting in the Torghut aristocracy in the west becoming Buddhists and sending their sons to monasteries and even Tibet. For example the Torghut prince Daichin made a pilgrimage to Tibet twice. And Zaya Pandita (1599-1662 AC), a foster son of the Khoshut Taijis Baibagas, studied in Tibet from 1616 AC on; when he returned home in 1639 AC he spread Buddhism among the tribes when he travelled through the country.
- In the 17th century, Zaya Pandita, a Gelug monk of the Khoshut tribe, devised a new writing system called Todo Bichig (clear script) to be used by the Oirat people. This system was developed on the basis of the older Mongolian script, but had a rather more developed diacritical system in order to exclude misreading; furthermore, it reflected some lexic and grammar differences of the Oirat language from the Mongolian one.
Some Oirats in China still use Todo Bichig as their primary writing system, apart from the Mongolian script.